A Retrospective Study on Survival in Palliative Gemcitabine Plus Carboplatin Versus Gemcitabine Plus Cisplatin for Biliary Tract Cancer Patients, Udonthani Cancer Hospital

Abstract

Gemcitabine plus cisplatin (gem/cis) has demonstrated a survival advantage over gemcitabine alone and become a standard regimen in advanced biliary tract cancer, but there was limitation of cisplatin in elderly or renal insufficient patients.  Carboplatin is another platinum chemotherapy that it showed efficacy in lung and ovarian cancer not inferior to cisplatin. There is no established comparative study between palliative gemcitabine plus carboplatin (gem/carbo) versus gem/cis in biliary tract cancer (BTC). This retrospective study aimed to compare the survival of palliative gem/carbo to gem/cis as the first line in BTC patients. The primary outcome was progression-free survival (PFS) and the second was overall survival (OS). A retrospective study in patients diagnosed BTC in Udonthani Cancer Hospital between January 2020 to June 2023. The patients received gemcitabine 1000 mg/m² D1, D8 and carboplatin AUC 4-5 D1 every 3 weeks (gem/carbo group) and gemcitabine 1000 mg/m² D1, D8 and cisplatin 25 mg/m² D1, D8 or cisplatin 75-80 mg/m² D1 every 3 weeks (gem/cis group)as the first line palliative chemotherapy. A retrospective study, data collection used electronic case record form. Data analyzed using descriptive statistics; frequency, precentage and inferential statistics by Kaplan-Meier method and log rank test.

Results: 78 pateints were included, 44 patients in the gem/carbo group (56.41%) and 34             patients in the gem/cis group (43.59%).Median progression-free survival (PFS) was 5.82 months       (95%CI; 2.81-8.83) in gem/carbo and 5.56 months (95%CI; 2.45-7.66) in gem/cis group with hazard  ratio (HR) =0.57 (95%CI; 0.34-1.00, p = 0.05). Median overall survival (OS) was 7.70 months (95%CI;5.81-9.60) and 5.92 months(95%CI; 4.22-7.62) in gem/carbo and gem/cis arm respectively. HR for median OS was 0.94 (95%CI; 0.59-1.49, p = 0.78)

Conclusions: Patients in gem/carbo group had longer median PFS and OS than those in gem/cis group. Gem/carbo regimen could be an alternative first line palliative chemotherapy to standard gem/cis, especially in patients who unsuitable for cisplatin.